By Toni Clarke and Ben Hirschler

                NEW YORK/LONDON  - An experimental drug derived from the
                saliva of the venomous Gila monster is one of a growing crop of new
                drugs that are being developed to improve memory and learning.

                The bite of the Gila monster -- a native lizard to the southwest
                United States and Mexico -- can be deadly but its saliva also
                contains a chemical which acts on a previously unknown receptor
                pathway in the brain that affects memory.

                The findings were presented on Thursday at the 7th International
                Geneva/Springfield Symposium on Advances in Alzheimer Therapy in
                Switzerland.

                New York-based biotechnology company Axonyx Inc., which is developing
                the drug, Gilatide, plans to start human trials with it as a
                treatment for Alzheimer's disease later this year.

                A growing number of companies are probing the mechanisms of memory
                formation, hoping to find drugs that can help offset memory loss in
                patients with diseases ranging from Alzheimer's to depression,
                schizophrenia, stroke, Parkinson's and AIDS.

                There are 500 million people in the world's major markets with
                diseases whose symptoms include memory loss, a market representing
                billions of dollars, according to industry estimates. There are
                millions more whose memory is impaired simply because of advancing
                age.

                One of the leaders in developing memory-enhancing drugs is Memory
                Pharmaceuticals, a privately held U.S. company founded by Eric
                Kandel, 72, a Columbia University researcher who won the Nobel Prize
                in 2000. Kandel began his experiments into memory with the Aplysia
                sea slug.

                Memory Pharmaceuticals has discovered several compounds that show
                promise in counteracting memory loss in animals and is hoping to
                start testing at least one in humans within a year. Memory's aim is
                not to root out the cause of diseases such as Alzheimer's -- the most
                common form of dementia -- but to treat the symptom of memory loss.

                "What we have are broader range drugs that would work in different
                diseases," said Tony Scullion, the company's chief executive.

                The race to develop a memory-enhancing elixir is one that big
                pharmaceuticals companies are determined also to be a part of, with
                Johnson & Johnson and Pfizer Inc. hoping their Alzheimer's drugs
                Reminyl and Aricept may also prove effective as memory drugs.

                But the small biotechnology companies are leading the way. Privately
                held Helicon Therapeutics, based in Farmingdale, New York and founded
                by Cold Spring Harbor Laboratory researcher Timothy Tully, is hoping
                to enter its compounds into human trials within two years.

                Tully's tests showed that fruit flies genetically engineered to
                produce more of a molecule known as CREB were able to remember a
                smell connected with an electric shock much longer than those
                genetically engineered to produce less CREB.

                A company traded on the American Stock Exchange, Cortex
                Pharmaceuticals Inc., is working on a class of compounds shown to
                increase the production in the brain of neurotrophin BDNF (brain
                derived neurotrophic factor), a substance apparently deficient in
                Alzheimer's patients.

                On Wednesday Cortex announced it has begun enrolling patients with
                mild cognitive impairment in a study to test its Ampakine compound.
                As many as 80 percent of patients with cognitive impairment go on to
                develop Alzheimer's over a five-year period, the company said.

                "The mechanism of action is totally different from that of the
                acetylcholinesterase class of drugs, the only FDA-approved treatment
                for Alzheimer's disease," said Vincent Simmon, chief executive of
                Cortex.

                The company's Ampakine compounds work to increase the strength of
                signals at connections between brain cells